Delasting device



1963 J. B. REID ETAL DELASTING DEVICE Original Filed Sept. 10, 1962 INVENTORS (/0 H/VB. 775/0 BY F70 5:? r ,4 Spare:

United States Patent 3,197,354 DELASTING DEVICE John B. Reid, Brighton, and Robert A. Spence, South Lincoln, Mass., assignors to Rain Corporation, Cambridge, Mass., a corporation of Massachusetts Griginal application Ser. No. 222,709, Sept. 10, 1962. Divided and this application Dec. 4, 1962, Ser. No.

2 Claims. (Cl. 12-15.1)

This invention generally relates to the manufacture of footwear and, more particularly, to a novel delasting device for detaching an insole of a shoe, or similar article of footwear, when it is adhesively adhered to the bottom of a shoe last as a step in the manufacturing procedure.

This application is a division of my copending application, Serial No. 222,709, filed September 10, 1962.

The desirability of easy removal of a shoe, or similar article of footwear, from its last as a step in the manufacture of the shoe is obvious and greatly desired by shoe manufacturers. The size of some shoes, the configurations of the lasts used and the fact a shoe may be very tightly pulled over and around the last as a part of the lasting operation may serve to make removal of the shoe a matter of some effort by the operator.

It is the primary object of the present invention to minimize the effort of the operator in pulling or separating the shoe from the last when the shoe has been adhesively secured to the last, whereby the adhesive bond between the shoe last bottom and the insole may be initially broken prior to any effort of the operator directed conventionally towards removing the shoe from the last.

Other objects and the entire scope of the present invention will become apparent from the following detailed description and by reference to the accompanying drawing. It should be understood, however, that the detailed description and specific examples, while indicating the preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent as the description herein progresses.

Reference now being made to the accompanying drawing which forms a part hereof, wherein like numerals refer to similar parts throughout, and in which:

FIGURE 1 is an exploded perspective view illustrating an air supply connection with a flexible wedge tip to sealably contact a complementary opening formed between the heel and forepart of the shoe last.

Referring now in detail to the drawing, FIGURE 1 generally illustrat s a last 12, of conventional configuration, the bottom surface 11 of which has been detachably secured to the inner foot contacting surface of an insole 14 which is located within shoe 15 by means of a doublefaced, pressure-sensitive adhesive in the form of a strip of tape 19 previously applied as a step in the manufacture of the shoe to form an assembled unit in the manner more fully described in our copending application Serial No. 150,037, filed November 3, 1961, now Patent No. 3,052,904, granted September 11, 1962, the disclosure of which is incorporated herein by reference, as a part hereof.

A charge of compressed air, acting upwardly against the insole 14 and downwardly against the bottom surface 11 of the last 12, exceeds the adhesive bond provided by the strip of double-faced, adhesive material 19, thereby breaking the adhesive bond and separating the last 12 from the insole 14.

In this action the insole 14 located within the shoe 15 balloons slightly away from the bottom surface 11 of the last 12. After the adhesive bond between the insole 14 and the last bottom 11 has been ruptured, the assembled shoe 15 may be pulled or removed from the last 12 in a conventional manner without damage to either element.

A charge of compressed-air is directed through inlet 27 into the space between the insole 14 and the last bottom surface 11 by a resiliently-sealed connection generally indicated by the numeral 35, as illustrated in FIGURE 1. This wedge-shaped connection is secured to the top of a hollow tube 29 which is, in turn, mounted rigidly on support 25 in the manner shown in FIGURE 1. A slot 39 is cut into the top surface 38 of the wedge connection 35 for clearance of the last hinge mechanism 39 when the wedge connection is inserted into the opening formed between the forepart 31 and the heel or rear portion 18 of the last 12 and the assembled unit is pressed downwardly against the connection 35 mounted on the tube 29. The connection 35 may be conveniently made of resilient rubber or other suitable material and serves as a seal between tube 20 and the last cavity 37 containing hinge mechanism 36 so that the cavity 37 serves as a passageway for directing the compressed air to the bottom surface 11 of last 12.

Cavity 37 containing the hinge 30 may constitute the only passage through the last and extends to the bottom portion thereof as best shown in FIGURE 1 at 40. In other words, the passage 37 will be simply through the hinge cavity formed in forepart 31 of the last or through the enlarged or extended opening formed in the bottom surface 11 at 313 of the last 12 as illustrated in FIG- URE 1.

In this invention, we break the attachment between the last and insole on either side of the adhesive tape 10 by the pneumatic pressure in the manner described. This pneumatic development is useful also in assisting an operator in pulling the assembled footwear from the last on which it has been assembled. Thus, the invention is not limited to instances where adhesive tape is used.

The pressure supplied to the pneumatic system through inlet 27 varies between 30 and lbs. guage. It will depend upon the area of the aligned insole and bottom portion or adjacent face of the last and strength of the adhesive. The time of application of the air pressure will usually be of the order of one second, more or less, and the volume of the air introduced likewise will be determined by the size of the shoe, the area of the tape connection, the strength of the adhesive as well as the pressure.

The present invention may thus be seen to completely and effectively accomplish the objects enumerated hereinabove by releasing the adhesive bond established with the double-faced, pressure-sensitive adhesive material interposed between an insole and bottom surface of a shoe last so that the assembled shoe may be easily and con veniently delasted from the shoe last without damage to either element. It will be realized, however, that various changes and substitutions may be made to the specific embodiments disclosed herein for the purpose of illustrating the principles of this invention without departing from these principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following appended claims.

We claim:

1. A delasting device comprising a last having an insole supporting bottom portion which includes separate rear and forepart members pivotally interconnected with each other to define a wedge-shaped opening therebetween, a passageway therein extending from the region of pivotal interconnection to said bottom portion, and means for introducing a charge of air to said passageway, said means including a member arranged to sealably fit within said opening between said portions, said member being provided with a passageway positioned to directly communicate with the previously mentioned passageway.

2. A connection for conducting a charge of air to the bottom surface of a last through a passageway extending from the region of pivotal interconnection between the rear and forepart portions, of said last comprising a resilient wedge-shaped member adapted to sealahly fit he- 5 tween said rear and forepart portions, said member having a recessed area formed therein to accommodate said pivotal interconnection and a passageway associated therewith arranged to directly communicate with the previously mentioned passageway when said connection and last are 10 assembled in interfitting engagement.

UNITED STATES PATENTS Pyke Jan. 30, 1900 Blake Jan. 11, 1921 Hadaway July 21, 1936 Grush Sept. 21, 1937 Grush Sept. 21, 1937 McDonald Mar. 31, 1942 Amico Apr. 2, 1957 Earnhardt June 13, 1961 Reid et a1. Sept. 11, 1962 

1. A DELASTING DEVICE COMPRISING A LAST HAVING AN IN SOLE SUPPORTING BOTTOM PORTION WHICH INCLUDES SEPARATE REAR AND FOREPART MEMBERS PIVOTALLY INTERCONNECTED WITH EACH OTHER TO DEFINE A WEDGE-SHAPED OPENING THEREBETWEEN, A PASSAGEWAY THEREIN EXTENDING FROM THE REGION OF PIVOTAL INTERCONNECTION TO SAID BOTTOM PORTION, AND MEANS FOR INTRODUCING A CHARGE OF AIR TO SAID PASSAGEWAY, SAID MEANS INCLUDING A MEMBER ARRANGED TO SEALABLY FIT WITHIN SAID OPENING BETWEEN SAID PORTIONS, SAID MEMBER BEING PROVIDED WITH A PASSAGEWAY POSITIONED TO DIRECTLY COMMUNICATE WITH THE PREVIOUSLY MENTIONED PASSAGEWAY. 